A method for efficiently depositing and preparing an amorphous carbon film based on regulating the surface phase composition of a nitrided layer matrix and its application

Abstract

The present invention relates to the technical field of composite coating preparation, and specifically relates to a method for efficiently depositing and preparing an amorphous carbon film based on the regulation of the surface phase composition of a nitrided layer matrix and its application. In the plasma nitriding system of the present invention, high-temperature plasma nitriding is utilized, followed by low-temperature plasma carbon film plating technology. By precisely regulating the surface phase composition and its relative content of the matrix nitrided layer, the efficient deposition of the subsequent amorphous carbon film is induced. This method can improve the growth efficiency of the carbon film and the film-substrate bonding force, obtain a friction-reducing and wear-resistant composite coating with excellent performance, thereby improving the friction and wear performance of workpieces, forming a low-cost composite technology for in-situ and efficiently preparing a nitrided layer / amorphous carbon film composite coating by one-step high-temperature plasma nitriding followed by low-temperature plasma carbon film plating in a plasma nitriding system, and applying it in key component fields such as mechanical and structural components.

Description

Technical Field

[0001] The present invention relates to the technical field of composite coating preparation, and particularly relates to a method for efficiently depositing and preparing an amorphous carbon film based on regulating the surface phase composition of a nitrided layer matrix and its application. Background Art

[0002] Diamond-like carbon (DLC) films are hard coatings with low friction coefficients, high wear resistance, and chemical inertness. Such amorphous carbon films are very attractive as solid lubricating films. However, due to high internal stress in the coating and large differences in thermal expansion coefficients between the coating and the substrate, they are prone to peeling off from the substrate during use, severely restricting their practical applications. Nitriding is a widely used surface strengthening technology for metals. The high-hardness nitrided surface layer can significantly improve the wear resistance of workpieces. The gradient hardness distribution endows the nitrided layer with excellent load-bearing capacity and fatigue performance. However, traditional composite surface treatment needs to be carried out in multiple devices and multiple processes. The multi-device and multi-process technology is difficult to ensure the stability and controllability of the quality of composite coatings, while reducing the preparation efficiency of composite coatings and increasing the preparation cost of composite coatings, hindering the large-scale preparation of composite coatings. In a plasma nitriding system, a composite layer of a nitrided layer + amorphous carbon film is prepared in situ by a one-step method through high-temperature nitriding followed by low-temperature plasma carbon film plating technology to improve the tribological properties of workpieces. However, in the technical combination of plasma nitriding and plasma carbon film plating, due to the influence of various factors on the type, distribution, and content of surface phases on the substrate surface after plasma nitriding, the quality, growth efficiency, and film-substrate bonding force of the subsequent in-situ deposited amorphous carbon film are uncontrollable problems.

[0003] In view of the above defects, the creators of the present invention have finally obtained the present invention through long-term research and practice. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem that in the technical combination of plasma nitriding and plasma carbon film plating, due to the influence of various factors on the type, distribution, and content of surface phases on the substrate surface after plasma nitriding, the quality, growth efficiency, and film-substrate bonding force of the subsequent in-situ deposited amorphous carbon film are uncontrollable, and to provide a method for efficiently depositing and preparing an amorphous carbon film based on regulating the surface phase composition of a nitrided layer matrix and its application.

[0005] To achieve the above purpose, the present invention discloses a method for efficiently depositing and preparing an amorphous carbon film based on regulating the surface phase composition of a nitrided layer matrix, including the following steps:

[0006] S1, Substrate pretreatment: Polish the surface of the substrate steel material with sandpaper to a mirror finish, and clean it in an alcohol and acetone solution for later use;

[0007] S2, High-temperature plasma nitriding: Put the sample obtained in step S1 into a plasma nitriding system for nitriding treatment. Introduce hydrogen or argon to raise the temperature. When the temperature reaches the set value, introduce the nitriding source gases nitrogen and hydrogen, control the gas pressure and the flow rate of the source gases, and carry out nitriding heat preservation.

[0008] S3, Argon ion plasma bombardment activation: After the nitriding heat preservation in step S2 ends, stop introducing the nitriding source gases, introduce argon, and achieve argon ion bombardment while the furnace temperature decreases.

[0009] S4, Low-temperature plasma carbon film plating: When the temperature drops below 200 °C, turn on the voltage, introduce the carbon source gas and hydrogen, control the gas pressure and the flow rates of the carbon source gas and hydrogen, and deposit the amorphous carbon film. After deposition, the sample is cooled to room temperature in the furnace and then taken out.

[0010] During the high-temperature plasma nitriding process in step S2, the gas pressure is 50 - 1000 Pa.

[0011] During the high-temperature plasma nitriding process in step S2, the flow rate ratio of hydrogen to nitrogen is 1:10 - 9:10, and the nitriding temperature is 350 - 600 °C.

[0012] During the high-temperature plasma nitriding process in step S2, the gas pressure is 220 Pa, the flow rate ratio of hydrogen to nitrogen is 1:3, and the nitriding temperature is 520 °C.

[0013] The nitrided layer obtained by high-temperature plasma nitriding in step S2 includes Fe 3 N and Fe 4 N phases.

[0014] For the argon ion plasma bombardment activation conditions in step S3, the argon flow rate is 5 - 25 sccm, the gas pressure is 30 - 150 Pa, the voltage is 600 - 800 V, and the activation time is 30 - 120 min. When the temperature drops to 200 °C, step S4 low-temperature plasma carbon film plating is carried out.

[0015] In step S4, the carbon source gas is any one of methane, ethane, propane, benzene, dimethyldichlorosilane, dimethylchlorosilane, trimethylchlorosilane, carbon monoxide, methanol, acetone, and alcohol.

[0016] In step S4, the deposition temperature is less than 200 °C, the deposition voltage is 750 - 850 V, and the deposition gas pressure is less than 100 Pa.

[0017] The present invention also discloses a nitrided layer / amorphous carbon film composite coating prepared by the above preparation method and the application of this nitrided layer / amorphous carbon film composite coating in mechanical and structural components.

[0018] During the plasma nitriding process, nitrogen molecules are dissociated and activated by the plasma in a nitrogen-hydrogen atmosphere, allowing nitrogen atoms to diffuse to the material surface. This nitrogen can create a nitrided zone consisting of a compound layer on the surface and a diffusion layer that grows into the subsurface of the material. The compound layer is composed of ε-Fe 3 N and γ’-Fe 4 N. The process parameters during nitriding have a significant impact on the composition and properties of the compound layer, especially the ratio of nitrogen to hydrogen (nitrogen-hydrogen ratio) in the atmosphere composition. Increasing the nitrogen-hydrogen ratio allows more nitrogen atoms to be used for diffusion, thereby increasing the nitrogen potential and making it easier to form the ε-Fe 3 N phase with a higher nitrogen content, while a lower nitrogen potential is more likely to form the γ’-Fe 4 N phase with a lower nitrogen content. Therefore, in this invention, under the same process parameters of nitriding temperature and nitriding time, the phase composition on the surface of the nitrided layer is regulated by varying the ratio of nitrogen to hydrogen.

[0019] Compared with the prior art, the beneficial effects of this invention are as follows: In the plasma nitriding system of this invention, high-temperature plasma nitriding is utilized, followed by low-temperature plasma carbon film plating technology. By precisely regulating the phase composition and its relative content on the surface of the substrate nitrided layer, the efficient deposition of the subsequent amorphous carbon film is induced. This method can improve the growth efficiency of the carbon film and the film-substrate bonding force, obtain a friction-reducing and wear-resistant composite coating with excellent performance, thereby improving the friction and wear performance of the workpiece, forming a low-cost composite technology for in-situ and efficient preparation of a nitrided layer / amorphous carbon film composite coating by one-step high-temperature plasma nitriding followed by low-temperature plasma carbon film plating in a plasma nitriding system, and applying it to key component fields such as mechanical and structural parts. Description of the Drawings

[0020] Figure 1 Raman test results of the amorphous carbon films in the examples and Comparative Examples 1, 2, 3, and 4;

[0021] Figure 2 XRD test results of the surface of the nitrided layers in the examples and Comparative Examples 1 and 2;

[0022] Figure 3 XRD test results of the surface of the nitrided layers in the examples and Comparative Examples 3 and 4;

[0023] Figure 4 TEM test results of the composite layers in the examples and Comparative Examples 1 and 2;

[0024] Figure 5 TEM test results of the composite layers in the examples and Comparative Examples 3 and 4;

[0025] Figure 6 TEM test results of the microregions at the interface of the composite layers in the examples and Comparative Examples 1 and 2;

[0026] Figure 7 Scratch test results of the composite layers of the examples and Comparative Examples 1 and 2;

[0027] Figure 8 Scratch test results of the composite layers of the examples and Comparative Examples 3 and 4;

[0028] Figure 9 Coefficient of friction test results of the composite layers of the examples and Comparative Examples 1 and 2;

[0029] Figure 10 Coefficient of friction test results of the composite layers of the examples and Comparative Examples 3 and 4;

[0030] Figure 11 Wear rate test results of the composite layers of the examples and Comparative Examples 1 and 2;

[0031] Figure 12 Wear rate test results of the composite layers of the examples and Comparative Examples 3 and 4. Detailed implementation manners

[0032] The following further elaborates on the above and other technical features and advantages of the present invention with reference to the accompanying drawings.

[0033] Example 1

[0034] In this example, the ratio of nitrogen gas to hydrogen gas in the plasma nitriding source gas was controlled to prepare a nitrided layer with a single Fe 3 N phase on the uppermost surface and a mixed phase of Fe 3 N and Fe 4 N in the subsurface, and then a low-temperature plasma carbon film was deposited, denoted as 0. The specific preparation method is as follows:

[0035] The surface of the alloy steel was polished with sandpaper to a mirror state, and after cleaning, it was placed in a plasma nitriding furnace for nitriding treatment. Nitrogen gas and hydrogen gas were respectively introduced as reaction gases, the ratio of nitrogen gas to hydrogen gas was 3:1, the voltage was 800V, the nitriding temperature was 520°C, the air pressure was 220Pa, and the holding time was 8h.

[0036] After the holding time ended, without turning off the voltage, the nitriding source gas valve was closed, and 15 sccm argon gas was introduced to bombard and activate the surface of the substrate nitrided layer. The voltage was reduced to 750V, the air pressure was set to 80Pa, and the sputtering time was 30min;

[0037] When the temperature dropped below 200°C, an amorphous carbon film was prepared. The argon gas valve was closed, propane and hydrogen gas were introduced as reaction gases, the deposition temperature was set to 160°C, the air pressure was set to 60Pa, and the deposition time was 5h. After the deposition time ended, the sample was cooled to room temperature in the furnace, and the sample was taken out for relevant characterization tests.

[0038] Comparative Example 1

[0039] In this comparative example, the ratio of nitrogen gas to hydrogen gas, the plasma nitriding source gases, was controlled to prepare a nitrided layer with the outermost surface and the subsurface phase compositions both being the Fe 3 N and Fe 4 N mixed phase, followed by a low-temperature plasma carbon coating, denoted as 1. The specific preparation method is as follows:

[0040] The surface of the alloy steel was polished to a mirror finish with sandpaper, and after cleaning, it was placed in a plasma nitriding furnace for nitriding treatment. Nitrogen gas and hydrogen gas were respectively introduced as reaction gases. The ratio of nitrogen gas to hydrogen gas was 1:1, the voltage was 800 V, the nitriding temperature was 520 °C, the gas pressure was 220 Pa, and the holding time was 8 h.

[0041] After the holding time ended, without turning off the voltage, the nitriding source gas valve was closed, and 15 sccm of argon gas was introduced to bombard and activate the surface of the substrate nitrided layer. The voltage was reduced to 750 V, the gas pressure was set to 80 Pa, and the sputtering time was 30 min;

[0042] When the temperature dropped below 200 °C, an amorphous carbon film was prepared. The argon gas valve was closed, and propane and hydrogen gas were introduced as reaction gases. The deposition temperature was set to 160 °C, the gas pressure was set to 60 Pa, and the deposition time was 5 h. After the deposition time ended, the sample was cooled to room temperature in the furnace, and the sample was taken out for relevant characterization tests.

[0043] Comparative Example 2

[0044] In this comparative example, the ratio of nitrogen gas to hydrogen gas, the plasma nitriding source gases, was controlled to prepare a nitrided layer with the outermost surface phase composition being a single Fe 4 N phase, and the subsurface being Fe 3 N and Fe 4 N mixed phase, followed by a low-temperature plasma carbon coating, denoted as 2. The specific preparation method is as follows:

[0045] The surface of the alloy steel was polished to a mirror finish with sandpaper, and after cleaning, it was placed in a plasma nitriding furnace for nitriding treatment. Nitrogen gas and hydrogen gas were respectively introduced as reaction gases. The ratio of nitrogen gas to hydrogen gas was 1:3, the voltage was 800 V, the nitriding temperature was 520 °C, the gas pressure was 220 Pa, and the holding time was 8 h.

[0046] After the holding time ended, without turning off the voltage, the nitriding source gas valve was closed, and 15 sccm of argon gas was introduced to bombard and activate the surface of the substrate nitrided layer. The voltage was reduced to 750 V, the gas pressure was set to 80 Pa, and the sputtering time was 30 min;

[0047] When the temperature drops below 200 °C, amorphous carbon film preparation is carried out. The argon gas valve is closed, and propane and hydrogen are introduced as reaction gases. The deposition temperature is set at 160 °C, the pressure is set at 60 Pa, and the deposition time is 5 h. After the deposition time ends, the sample is cooled to room temperature in the furnace, and the sample is taken out for relevant characterization tests.

[0048] Comparative Example 3

[0049] In this comparative example, the ratio of nitrogen gas to hydrogen gas, the plasma nitriding source gases, was controlled to prepare a nitrided layer with the outermost surface and the subsurface phase compositions both being the mixed phase of Fe 3 N and Fe 4 N, followed by low-temperature plasma carbon coating, denoted as 3. The specific preparation method is as follows:

[0050] The surface of the alloy steel was polished to a mirror state with sandpaper, and after cleaning, it was placed in a plasma nitriding furnace for nitriding treatment. Nitrogen and hydrogen were introduced as reaction gases respectively. The ratio of nitrogen to hydrogen was 3:1, the voltage was 800 V, the nitriding temperature was 490 °C, the pressure was 220 Pa, and the holding time was 8 h.

[0051] After the holding time ended, without turning off the voltage, the nitriding source gas valve was closed, and 15 sccm of argon was introduced to bombard and activate the surface of the nitrided layer of the substrate. The voltage was reduced to 750 V, the pressure was set at 80 Pa, and the sputtering time was 30 min;

[0052] When the temperature drops below 200 °C, amorphous carbon film preparation is carried out. The argon gas valve is closed, and propane and hydrogen are introduced as reaction gases. The deposition temperature is set at 160 °C, the pressure is set at 60 Pa, and the deposition time is 5 h. After the deposition time ends, the sample is cooled to room temperature in the furnace, and the sample is taken out for relevant characterization tests.

[0053] Comparative Example 4

[0054] In this comparative example, the ratio of nitrogen gas to hydrogen gas, the plasma nitriding source gases, was controlled to prepare a nitrided layer with the outermost surface and the subsurface phase compositions both being the mixed phase of Fe 3 N and Fe 4 N, followed by low-temperature plasma carbon coating, denoted as 4. The specific preparation method is as follows:

[0055] The surface of the alloy steel was polished to a mirror state with sandpaper, and after cleaning, it was placed in a plasma nitriding furnace for nitriding treatment. Nitrogen and hydrogen were introduced as reaction gases respectively. The ratio of nitrogen to hydrogen was 3:1, the voltage was 800 V, the nitriding temperature was 460 °C, the pressure was 220 Pa, and the holding time was 8 h.

[0056] After the holding time ends, without turning off the voltage, close the nitriding source gas valve, introduce 15 sccm argon gas to bombard and activate the surface of the substrate nitrided layer, reduce the voltage to 750 V, set the gas pressure to 80 Pa, and the sputtering time is 30 min;

[0057] When the temperature drops below 200 °C, prepare the amorphous carbon film. Close the argon gas valve, introduce propane and hydrogen as reaction gases, set the deposition temperature to 160 °C, set the gas pressure to 60 Pa, and the deposition time is 5 h. After the deposition time ends, the sample is cooled to room temperature in the furnace, and the sample is taken out for relevant characterization tests.

[0058] The performance characterizations of the 0, 1, 2, 3, and 4 composite layers prepared in the above examples and Comparative Examples 1, 2, 3, and 4 are as follows: Use a Raman spectrometer to test the carbon film and analyze the carbon atom bonding components, such as Figure 1 shown Figure 1 are the Raman spectra of the amorphous carbon films in the examples and Comparative Examples 1, 2, 3, and 4. The results show obvious D peaks and G peaks, which are the characteristics of typical amorphous carbon films.

[0059] Use an X-ray diffractometer (XRD) to detect the surface phase structure of the nitrided layer. Select Cu-Kα target radiation, the 2θ angle range is 20° to 90°, the step size is 0.02°, the voltage is 30 kV, and the current is 20 mA. Such as Figure 2 and 3 shown Figure 2 are the XRD phase test results of the surfaces in the examples and Comparative Examples 1 and 2, Figure 3 are the XRD phase test results of the surfaces in the examples and Comparative Examples 3 and 4. It can be seen from the results that the surfaces of the nitrided layers in the examples and Comparative Examples 1, 2, 3, and 4 are all composed of α N , Fe 3 N and Fe 4 N phases, but the relative contents of each phase vary greatly. Use Jade software to fit and calculate the relative contents of the Fe 3 N phase and the Fe 4 N phase for each peak intensity. The results show that the content of the Fe 3 N phase on the surface of the nitrided layer in the example is as high as 87.3%, while the contents of the Fe 3 N phase on the surfaces of the nitrided layers in Comparative Examples 1, 2, 3, and 4 are 72.8%, 35.5%, 78.9%, and 52% respectively, all lower than that of the example. It shows that the phase composition and relative content of the surface of the nitrided layer can be regulated by changing the nitriding conditions, thereby affecting the subsequent deposition of the amorphous carbon film and the film-substrate bonding force.

[0060] Use a transmission electron microscope (TEM) to test and analyze the cross-section of the composite layer, such as Figure 4 and 5 shownFigure 4 TEM test results of the composite layers of the examples and Comparative Examples 1 and 2. (a) Cross-sectional morphology of the composite layer of the example; (b) Cross-sectional morphology of the composite layer of Comparative Example 1; (c) Cross-sectional morphology of the composite layer of Comparative Example 2. Figure 5 TEM test results of the composite layers of the examples and Comparative Examples 3 and 4. (a) Cross-sectional morphology of the composite layer of the example; (b) Cross-sectional morphology of the composite layer of Comparative Example 3; (c) Cross-sectional morphology of the composite layer of Comparative Example 4. It can be seen that the thickness of the amorphous carbon film deposited in the example reached nearly 2 μm, while the thicknesses of the amorphous carbon films deposited in Comparative Examples 1, 2, 3, and 4 were only about 1.02 μm, 0.37 μm, 1.17 μm, and 0.79 μm, respectively. The results show that the surface phase composition and content of the nitrided layer have a great influence on the thickness of the subsequently deposited amorphous carbon film. The more the content of Fe 3 N phase on the surface of the nitrided layer, the higher the growth efficiency of the carbon film.

[0061] The transmission electron microscope (TEM) was used to test and analyze the micro-region of the composite layer interface, as Figure 6 shown. Figure 6 TEM test results of the micro-region of the composite layer interface of the examples and Comparative Examples 1 and 2. (a) Bright-field TEM image of the micro-region of the composite layer interface of Comparative Example 1. The selected electron diffraction pattern inserted inside contains diffraction rings of Fe4N and Fe3N, corresponding to the (111) and (210) planes of Fe 4 N; the (202), (211), and (113) planes of Fe 3 N. The results show that the nitrided layer obtained by high-temperature plasma nitriding is composed of Fe 3 N and Fe 4 N phases. (b), (c), and (d) are the high-resolution images of the micro-region of the interface of the example and Comparative Examples 1 and 2, respectively. The corresponding inverse Fourier transform results are inserted inside. It can be seen from Figure (b) that the uppermost surface of the nitrided layer in the example is a single Fe 3 N phase, and there is a continuous transition zone between the nitrided layer and the amorphous carbon film. Figure (c) shows that the uppermost surface and the subsurface of the nitrided layer in Comparative Example 1 are both composed of a mixed phase of Fe3N and Fe4N. The results of Comparative Examples 3 and 4 are similar to those of Comparative Example 1 and are not listed here. Figure (d) shows that the uppermost surface of the nitrided layer in Comparative Example 2 is a single Fe 4 N phase, and the subsurface is composed of a mixed phase of Fe 3 N and Fe 4 N.

[0062] The scratch test method was used to evaluate the adhesion between the carbon film and the substrate through the acoustic signal and the scratch morphology. The loading force was 1 - 100 N, and the loading rate was 100 N / min, as Figure 7 and 8 shown. Figure 7Scratch test results of the composite layers of the examples and Comparative Examples 1 and 2. (a) is the composite layer of the example, with a bonding strength of 94.43 N. (b) is the composite layer of Comparative Example 1, with a bonding strength of 51.45 N. (c) is the composite layer of Comparative Example 2, with a bonding strength of 32.01 N. Figure 8 Scratch test results of the composite layers of the examples and Comparative Examples 3 and 4. (a) is the composite layer of the example, with a bonding strength of 94.43 N. (b) is the composite layer of Comparative Example 3, with a bonding strength of 55.56 N. (c) is the composite layer of Comparative Example 4, with a bonding strength of 45.69 N. It can be seen that the bonding force of the example is higher than that of Comparative Examples 1, 2, 3, and 4, indicating that the surface phase composition and content of the nitrided layer also have a great influence on the bonding force of the composite layer. The Fe 3 The more the N phase content on the surface of the nitrided layer, the higher the film-substrate bonding force of the composite layer.

[0063] The friction and wear performance of the composite layer was tested using a ball-on-disk friction and wear tester. The friction pair was an alumina ball (diameter Φ = 6.35 mm), the load was 1 N, the wear radius was 2 mm, the rotation speed was 240 r / min, the test time was 2000 s, and the test temperature was room temperature. By analyzing the change of the friction coefficient curve, the growth of the amorphous carbon film and the friction and wear performance of the composite layer can be determined. For example, Figure 9 and 10 shown, Figure 9 are the friction coefficient curves of the composite layers of the examples and Comparative Examples 1 and 2; Figure 10 are the friction coefficient curves of the composite layers of the examples and Comparative Examples 3 and 4. It can be seen from the figure that the friction coefficient of the composite layer of Comparative Example 2 began to increase at the beginning of sliding and continued to increase to more than 0.4, indicating that the carbon film was very thin and worn through. The friction coefficient of the composite layer of Comparative Example 4 gradually stabilized within a range below 0.2 after a slight increase at the beginning stage, indicating that the carbon film had slight wear. The friction coefficients of the examples and Comparative Examples 1 and 3 stabilized within a range below 0.1 after a short decrease after the start of sliding, indicating that the carbon film was intact and the composite layer exhibited excellent friction and wear performance. The wear rate was calculated by fitting the wear marks using a probe-type profilometer stress gauge. For example, Figure 11 and 12 shown, Figure 11 are the wear rate calculation results of the composite layers of the examples and Comparative Examples 1 and 2; Figure 12 are the wear rate calculation results of the composite layers of the examples and Comparative Examples 3 and 4. It can be seen from the figure that the wear rate of Comparative Example 2 is much higher than that of the examples and Comparative Examples 1 and 3, indicating that the carbon film thickness of the composite layer of Comparative Example 2 is thinner. Combining the friction coefficient results, it can be known that the surface phase composition and content of the nitrided layer have a great influence on the deposition and growth of the subsequent amorphous carbon film and the friction and wear performance of the composite layer. The Fe 3 N phase rather than Fe 4The N phase can promote the growth of the amorphous carbon film and improve the film-substrate bonding force. By regulating the surface phase composition of the nitrided layer, a nitrided layer / amorphous carbon film composite coating with excellent anti-friction and wear-resistant properties can be efficiently prepared.

[0064] The above are only the preferred embodiments of the present invention, which are illustrative rather than restrictive to the present invention. Those skilled in the art understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, but all will fall within the protection scope of the present invention.

Claims

1. A method for efficiently depositing and preparing an amorphous carbon film by regulating the surface phase composition of a nitrided layer matrix, characterized in that, it includes the following steps: S1, Substrate pretreatment: Polish the surface of the substrate steel material with sandpaper until it becomes mirror-like, and clean it in an alcohol and acetone solution for standby; S2, High-temperature plasma nitriding: Put the sample obtained in step S1 into a plasma nitriding system for nitriding treatment. Introduce hydrogen or argon to raise the temperature. When the temperature rises to the set value, introduce the nitriding source gases nitrogen and hydrogen, control the air pressure and the flow rate of the source gases, and carry out nitriding heat preservation; S3, Argon ion plasma bombardment activation: After the nitriding heat preservation in step S2 ends, stop introducing the nitriding source gas, introduce argon, and realize argon ion bombardment while the furnace temperature decreases; S4, Low-temperature plasma carbon film plating: When the temperature drops below 200 °C, turn on the voltage, introduce the carbon source gas and hydrogen, control the air pressure and the flow rates of the carbon source gas and hydrogen, and deposit the amorphous carbon film. After deposition, the sample is cooled to room temperature in the furnace and then taken out; In the high-temperature plasma nitriding process in step S2, the ratio of nitrogen to hydrogen is 3:1, the voltage is 800 V, the nitriding temperature is 520 °C, the air pressure is 220 Pa, and the heat preservation time is 8 h.

2. A method for efficiently depositing and preparing an amorphous carbon film by regulating the surface phase composition of a nitrided layer matrix as described in claim 1, characterized in that, The upper surface phase composition of the nitrided layer obtained by high-temperature plasma nitriding in the step S2 is a single Fe 3 N phase, and the subsurface is Fe 3 N and Fe 4 N mixed phase.

3. A method for efficiently depositing and preparing an amorphous carbon film by regulating the surface phase composition of a nitrided layer matrix as described in claim 1, characterized in that, For the argon ion plasma bombardment activation conditions in step S3, the argon gas flow rate is 5 - 25 sccm, the air pressure is 30 - 150 Pa, the voltage is 600 - 800 V, the activation time is 30 - 120 min, and step S4 low-temperature plasma carbon film plating is carried out when the temperature drops to 200 °C.

4. A method for efficiently depositing and preparing an amorphous carbon film by regulating the surface phase composition of a nitrided layer matrix as described in claim 1, characterized in that, The carbon source gas in step S4 is any one of methane, ethane, propane, benzene, dimethyldichlorosilane, dimethylchlorosilane, trimethylchlorosilane, carbon monoxide, methanol, acetone, and alcohol.

5. A method for efficiently depositing and preparing an amorphous carbon film by regulating the surface phase composition of a nitrided layer matrix as described in claim 1, characterized in that, In step S4, the deposition temperature is less than 200 °C, the deposition voltage is 750 - 850 V, and the deposition air pressure is less than 100 Pa.

6. A nitrided layer / amorphous carbon film composite coating prepared by using the method for efficiently depositing and preparing an amorphous carbon film by regulating the surface phase composition of a nitrided layer matrix as described in any one of claims 1 - 5.

7. An application of the nitrided layer / amorphous carbon film composite coating as described in claim 6 in mechanical and structural components.

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